1. Field of the Invention
The present invention is generally concerned with ultraviolet radiation drying ovens of the kind comprising, successively staggered along a conveyor adapted to carry objects to be dried, a loading station to which said objects must be introduced, a drying enclosure containing at least one ultraviolet radiation lamp and an offloading station from which the dried objects are evacuated.
Drying ovens of this kind are used, for example, at the outlet end of a printing machine when the objects concerned are printed with a ploymerizable ink.
2. Description of the Prior Art
One problem to be overcome in producing drying ovens of this type concerns the necessity to prevent ultraviolet radiation escaping from the oven, in order to protect the operator.
At the offloading station, where it may be sufficient for the dried objects to be tipped loose in bulk by gravity, a cover over the respective end of the conveyor leaving between the conveyor and its own end wall a gap sufficient for the objects to fall through is simple and satisfactory.
The same cannot be said of the loading station end where it is further necessary to provide for adequate separation of the objects from each other so that they do not soil each other.
In one prior art drying oven of this kind the ultraviolet radiation is blocked at this location by disposing between the loading station and the drying enclosure a relatively long and angular tunnel along which the objects to be dried are fed by the conveyor in contact with a guide.
This arrangement has numerous disadvantages.
First of all, given the length required of the tunnel, it produces a relatively large and relatively costly assembly.
Also, given the inevitable uncertainty as to the effects of friction arising within the tunnel between the objects to be dried and the guide with which they are in contact as they move along, the objects may be soiled if they unintentionally catch up with each other.
An object of the present invention, in a first aspect, is an arrangement providing a very simple way to meet the two-fold requirement of blocking ultraviolet radiation and separating the objects to be dried.